As soon as time expired on the vice presidential debate, the rush was on to answer the question: Who won?

No doubt, many Democrats said, Joe Biden had the better showing. Republicans were equally certain, saying that Paul Ryan prevailed. Both campaigns blasted emails in bunches, quoting an assortment of surrogates and character witnesses who affirmed that their party’s candidate had emerged victorious.

Despite these concerted efforts to establish an advantage, the vice presidential debate appears unlikely to shift the campaign narrative or to move the polls the way the first Mitt Romney-Barack Obama match-up did. In the days leading up to the running mate debate, much was said and written about how Biden vs. Ryan could be unusually consequential. The meeting of the vice-presidential candidates came at pivotal moment in the presidential campaign, as Mr. Romney was riding a wave of momentum coming out of his own debate, and Mr. Obama’s team was regrouping after the president’s low-energy performance.

For Democrats, the hope heading into the vice presidential debate was that Mr. Biden would aggressively attack the GOP ticket while avoiding a significant gaffe. For Republicans, the objective for Mr. Ryan, a 42-year-old congressman from Janesville, Wis., was to show that he has the experience and gravitas required in this job.

Each campaign has argued that its candidate achieved his goal. Mr. Biden managed to settle Democrats’ nerves. And Mr. Ryan appeared well prepared for his moment under the bright lights.

Pundits will continue to discuss Mr. Biden’s gesticulations and Mr. Ryan’s need to hydrate during the debate. But these are questions of style, not substance.

Any impact the vice presidential debate might have on the polls would take several days to emerge. But by then, Mr. Romney and Mr. Obama already will have debated again. They’ll meet Tuesday at Hofstra University in New York.

With another presidential debate just a few days away, storylines from the vice presidential face-off will fade as the discussion about whether Mr. Obama can rebound resumes. Mr. Biden’s performance is providing a brief respite from the hashing and rehashing of what the president called a “bad night.” But even most Democrats aren’t suggesting that the vice president reset the race.

As a result, Mr. Obama will find himself in much the same place after the vice presidential debate as he was before: in a tight race with time running short. The Real Clear Politics’ average of national polls now shows Mr. Romney leading, 47% to 46%. Mr. Obama still leads in several key battlegrounds, but those margins have narrowed as well.

Messrs. Ryan and Biden provided voters with 90 minutes’ worth of detailed policy discussions and pointed disagreements. But with both sides declaring victory and the next presidential debate fast approaching, the onus is back on Mr. Romney to build on his campaign’s momentum and on the president to deliver a stronger showing the second time around.

About Washington Wire

Washington Wire is one of the oldest standing features in American journalism. Since the Wire launched on Sept. 20, 1940, the Journal has offered readers an informal look at the capital. Now online, the Wire provides a succession of glimpses at what’s happening behind hot stories and warnings of what to watch for in the days ahead. The Wire is led by Reid J. Epstein, with contributions from the rest of the bureau. Washington Wire now also includes Think Tank, our home for outside analysis from policy and political thinkers.